During an asthma attack, also called an asthma exacerbation, your airways become swollen and inflamed. The muscles around the airways contract, causing your breathing (bronchial) tubes to narrow.

During an asthma attack, you may cough, wheeze and have trouble breathing. An asthma attack may be minor, with symptoms that get better with prompt home treatment, or it may be more serious. A severe asthma attack that doesn't improve with home treatment can become a life-threatening emergency.

The key to stopping an asthma attack is recognizing and treating an asthma flare-up early. Follow the treatment plan you worked out with your doctor ahead of time. This plan should include what to do when your asthma starts getting worse, and how to deal with an asthma attack in progress.

Asthma attack signs and symptoms include:

Severe shortness of breath, chest tightness or pain, and coughing or wheezing

Low peak expiratory flow (PEF) readings, if you use a peak flow meter

Worsening symptoms despite use of a quick-relief (rescue) inhaler

Signs and symptoms of an asthma attack vary from person to person. Work with your doctor to identify your particular signs and symptoms of worsening asthma — and what to do when they occur.

If your asthma symptoms keep getting worse even after you take medication as your doctor directed, you may need a trip to the emergency room. Your doctor can help you learn to recognize an asthma emergency so that you'll know when to get help.

When to see the doctor

If your asthma flares up, immediately follow the treatment steps you and your doctor worked out ahead of time in your written asthma plan. If your symptoms and peak expiratory flow (PEF) readings improve, home treatment may be all that's needed. If your symptoms don't improve with home treatment, you may need to seek emergency care.

When your asthma symptoms flare up, follow your written asthma plan's instructions for using your quick-acting (rescue) inhaler. If you use a peak flow meter to monitor your asthma, PEF readings ranging from 50 to 79 percent of your personal best are a sign you need to use quick-acting (rescue) medications prescribed by your doctor.

Check asthma control steps with your doctor

Asthma can change over time, so you'll need periodic adjustments to your treatment plan to keep daily symptoms under control. If your asthma isn't well controlled, it increases your risk of future asthma attacks. Lingering lung inflammation means your asthma could flare up at any time.

Go to all scheduled doctor's appointments. If you have regular asthma flare-ups, low peak flow readings or other signs your asthma isn't well controlled, make an appointment to see your doctor.

When to seek emergency medical treatment

Seek medical attention right away if you have signs or symptoms of a serious asthma attack, which include:

Severe breathlessness or wheezing, especially at night or in the early morning

The inability to speak more than short phrases due to shortness of breath

For many people, asthma symptoms get worse with a respiratory infection such as a cold. Some people have asthma flare-ups caused by something in their work environment. Sometimes, asthma attacks occur with no apparent cause.

Anyone who has asthma is at risk of an asthma attack. You may be at increased risk of a serious asthma attack if:

You've had a severe asthma attack in the past

You've previously been admitted to the hospital or had to go to the emergency room for asthma

You use more than two quick-relief (rescue) inhalers a month

Your asthma attacks tend to "sneak up" on you before you notice symptoms have worsened

You have other chronic health conditions, such as sinusitis or nasal polyps

Asthma attacks can be serious.

Asthma attacks can interrupt everyday activities such as sleep, school, work and exercise, causing a significant impact on your quality of life — and can disrupt the lives of those around you.

Serious asthma attacks mean you're likely to need trips to the emergency room, which can be stressful and costly.

A very severe asthma attack can lead to respiratory arrest and death.

Be prepared for your visit to your doctor so that you can get the most out of your appointment. At each visit:

Take your asthma action plan with you when you see your doctor. If you haven't made one yet, work with your doctor to create one. This plan should discuss how to treat an asthma attack.

Include your peak flow meter results and all of your medications.

Be prepared to discuss your symptoms, and how much your asthma has been bothering you. Often, periodic changes in treatment are needed to keep asthma under control and to prevent asthma attacks.

Be prepared to demonstrate using your metered-dose inhaler. Improper use can reduce an inhaler's effectiveness.

Your time with your doctor is limited, so preparing a list of questions will help you make the most of your time together. Some good questions to ask your doctor include:

Do my medications or treatment plan need to be changed?

What are the signs that I may be about to have an asthma attack?

What can I take to prevent an asthma attack when my symptoms get worse, or when I'm exposed to my triggers?

What steps do I need to take to stop an asthma attack in progress?

When do I need to go to the emergency room or seek other emergency treatment?

I'm having more heartburn. What can I do to prevent this?

Is it time for my flu shot? Am I due for a pneumonia shot?

What else can I do to protect my health during cold and flu season?

In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment.

What to expect from your doctor

Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to spend more time on. Your doctor may ask:

Have you noticed anything that makes your asthma worse?

What medications are you taking?

How and when are you taking them?

Can you show me how you use your inhaled medication?

Are you having any problems with your medications?

Do you know when to call me or go to the hospital?

Do you have any questions about your asthma action plan?

Are you having any problems with your asthma action plan?

Is there anything you want to be able to do that you can't because of your asthma?

For adults and children over 5 years old, lung (pulmonary) function tests are used to check how well the lungs are working. Poor lung function is a sign that your asthma isn't well controlled. In some cases, lung function tests are used in asthma emergencies to help check the severity of an asthma attack or how well treatment is working.

Lung function tests include:

Peak flow. Your doctor may take a peak flow reading when you come in for a scheduled visit or for emergency treatment during an asthma attack. This test measures how quickly you can breathe out. You may also use a peak flow meter at home to monitor your lung function.

The results of this test are known as peak expiratory flow (PEF). A peak flow test is done by blowing into a mouthpiece as hard and as fast as you can with a single breath (expiration).

Spirometry. During spirometry, you take deep breaths and forcefully exhale into a hose connected to a machine called a spirometer. A common spirometry measurement is forced expiratory volume, which measures how much air you can breathe out in one second.

The results of this test are known as forced expiratory volume (FEV). Spirometry can also measure how much air your lungs can hold and the rate at which you can inhale and exhale.

Nitric oxide measurement. A newer diagnostic test, this exam measures the amount of nitric oxide gas you have in your breath. High nitric oxide readings indicate inflammation of the bronchial tubes.

To do this test, you exhale slowly into a mouthpiece attached to an electronic measurement device. This device is attached to a computer with a monitor that displays your test results.

Pulse oximetry. This test is used during a severe asthma attack. It measures the amount of oxygen in your blood. It's measured through your fingernail and only takes seconds.

If you're having an asthma attack, follow the steps in the asthma plan you worked out with your doctor. If your symptoms don't improve, seek immediate medical care.

Home treatment steps to stop an asthma attack generally include taking 2.5 to 5 milligrams of albuterol (ProAir HFA, Ventolin HFA, others) every 20 minutes for an hour. You may also use a different quick-acting medication. Generally, less medication is needed for children and in adults with less severe symptoms.

Your plan for treating an asthma attack at home may include oral corticosteroid medication such as prednisone. Ask your doctor if a plan for home corticosteroid treatment of an asthma attack is right for you.

If you use a peak flow meter to monitor your asthma, peak expiratory flow readings ranging from 50 to 79 percent of your personal best are a sign you need to use albuterol or other quick-acting (rescue) inhaler medication. Routinely checking your peak flow readings is important because your lung function may decrease before you notice any other signs or symptoms of worsening asthma.

Emergency treatment

If you go to the emergency room for an asthma attack in progress, you'll need medications to get your asthma under immediate control. These can include:

Short-acting beta agonists, such as albuterol. These medications are the same medications as those in your quick-acting (rescue) inhaler. You may need to use a machine called a nebulizer, which turns the medication into a mist that can be inhaled deep into your lungs.

Oral corticosteroids. Taken in pill form, these medications help reduce lung inflammation and get your asthma symptoms under control. For more-severe asthma attacks, corticosteroids can be given intravenously.

Ipratropium (Atrovent). Ipratropium is sometimes used as a bronchodilator to treat a severe asthma attack, especially if albuterol is not fully effective.

Intubation, mechanical ventilation and oxygen. If your asthma attack is life-threatening, your doctor may put a breathing tube down your throat into your upper airway. Using a machine that pumps oxygen into your lungs will help you breathe while your doctor gives you medications to get your asthma under control.

After your asthma symptoms get better, your doctor may want you to stay in the emergency room for a few hours or longer to make sure you don't have another asthma attack. When your doctor feels your asthma is sufficiently under control, you'll be able to go home. Your doctor will give you instructions on what to do if you have another asthma attack.

If your asthma symptoms don't improve after emergency treatment, your doctor may admit you to the hospital and give you medications every hour or every few hours. If you're having severe asthma symptoms, you may need to breathe oxygen through a mask. In some cases, a severe, persistent asthma attack requires a stay in the intensive care unit (ICU).

All asthma attacks require treatment with a quick-acting (rescue) inhaler such as albuterol. One of the key steps in preventing an asthma attack is to avoid your triggers.

If your asthma attacks seem to be set off by outside triggers, your doctor can help you learn how to minimize your exposure to them. Allergy tests can help identify your allergic triggers.

If your asthma flares up when you exercise in the cold, it may help to cover your face with a mask or scarf until you get warmed up.

The best way to avoid an asthma attack is to make sure your asthma is well controlled in the first place. This means following a written asthma plan to track symptoms and adjust your medication.

While you may not be able to eliminate your risk of an asthma attack, you're less likely to have one if your current treatment keeps your asthma under control. Take your inhaled medications as prescribed in your written asthma plan.

These preventive medications treat the airway inflammation that causes asthma signs and symptoms. Taken on a daily basis, these medications can reduce or eliminate asthma flare-ups — and your need to use a quick-relief inhaler.

See your doctor if you're following your asthma action plan but you still have frequent or bothersome symptoms or low peak flow readings. This is a sign that your asthma isn't well controlled, and you need to work with your doctor to change your treatment.

If your asthma symptoms flare up when you have a cold or the flu, take steps to avoid an asthma attack by watching your lung function and symptoms and adjusting your treatment as needed. Be sure to reduce exposure to your allergy triggers. And when exercising in cold weather, wear a face mask.

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